Mercurial > hg > octave-nkf
changeset 5183:cfd451656707
[project @ 2005-03-03 06:30:04 by jwe]
author | jwe |
---|---|
date | Thu, 03 Mar 2005 06:30:04 +0000 |
parents | 5b361aa47dff |
children | d35c5104ffbe |
files | scripts/strings/str2double.m |
diffstat | 1 files changed, 267 insertions(+), 0 deletions(-) [+] |
line wrap: on
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new file mode 100644 --- /dev/null +++ b/scripts/strings/str2double.m @@ -0,0 +1,267 @@ +function [num,status,strarray] = str2double(s,cdelim,rdelim,ddelim) +%% STR2DOUBLE converts strings into numeric values +%% [NUM, STATUS,STRARRAY] = STR2DOUBLE(STR) +%% +%% STR2DOUBLE can replace STR2NUM, but avoids the insecure use of EVAL +%% on unknown data [1]. +%% +%% STR can be the form '[+-]d[.]dd[[eE][+-]ddd]' +%% d can be any of digit from 0 to 9, [] indicate optional elements +%% NUM is the corresponding numeric value. +%% if the conversion fails, status is -1 and NUM is NaN. +%% STATUS = 0: conversion was successful +%% STATUS = -1: couldnot convert string into numeric value +%% STRARRAY is a cell array of strings. +%% +%% Elements which are not defined or not valid return NaN and +%% the STATUS becomes -1 +%% STR can be also a character array or a cell array of strings. +%% Then, NUM and STATUS return matrices of appropriate size. +%% +%% STR can also contain multiple elements. +%% default row-delimiters are: +%% NEWLINE, CARRIAGE RETURN and SEMICOLON i.e. ASCII 10, 13 and 59. +%% default column-delimiters are: +%% TAB, SPACE and COMMA i.e. ASCII 9, 32, and 44. +%% default decimal delimiter is '.' char(46), sometimes (e.g in +%% Tab-delimited text files generated by Excel export in Europe) +%% might used ',' as decimal delimiter. +%% +%% [NUM, STATUS] = STR2DOUBLE(STR,CDELIM,RDELIM,DDELIM) +%% CDELIM .. [OPTIONAL] user-specified column delimiter +%% RDELIM .. [OPTIONAL] user-specified row delimiter +%% DDELIM .. [OPTIONAL] user-specified decimal delimiter +%% CDELIM, RDELIM and DDELIM must contain only +%% NULL, NEWLINE, CARRIAGE RETURN, SEMICOLON, COLON, SLASH, TAB, SPACE, COMMA, or ()[]{} +%% i.e. ASCII 0,9,10,11,12,13,14,32,33,34,40,41,44,47,58,59,91,93,123,124,125 +%% +%% Examples: +%% str2double('-.1e-5') +%% ans = -1.0000e-006 +%% +%% str2double('.314e1, 44.44e-1, .7; -1e+1') +%% ans = +%% 3.1400 4.4440 0.7000 +%% -10.0000 NaN NaN +%% +%% line ='200,300,400,NaN,-inf,cd,yes,no,999,maybe,NaN'; +%% [x,status]=str2double(line) +%% x = +%% 200 300 400 NaN -Inf NaN NaN NaN 999 NaN NaN +%% status = +%% 0 0 0 0 0 -1 -1 -1 0 -1 0 +%% +%% Reference(s): +%% [1] David A. Wheeler, Secure Programming for Linux and Unix HOWTO. +%% http://en.tldp.org/HOWTO/Secure-Programs-HOWTO/ + +%% This program is free software; you can redistribute it and/or +%% modify it under the terms of the GNU General Public License +%% as published by the Free Software Foundation; either version 2 +%% of the License, or (at your option) any later version. +%% +%% This program is distributed in the hope that it will be useful, +%% but WITHOUT ANY WARRANTY; without even the implied warranty of +%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +%% GNU General Public License for more details. +%% +%% You should have received a copy of the GNU General Public License +%% along with this program; if not, write to the Free Software +%% Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +%% $Revision: 1.11 $ +%% $Id: str2double.m,v 1.11 2004/06/23 20:52:32 schloegl Exp $ +%% Copyright (C) 2004 by Alois Schloegl <a.schloegl@ieee.org> +%% This function is part of Octave-Forge http://octave.sourceforge.net/ + +FLAG_OCTAVE = exist('OCTAVE_VERSION','builtin'); + +% valid_char = '0123456789eE+-.nNaAiIfF'; % digits, sign, exponent,NaN,Inf +valid_delim = char(sort([0,9:14,32:34,abs('()[]{},;:"|/')])); % valid delimiter +if nargin < 1, + error('missing input argument.') +end; +if nargin < 2, + cdelim = char([9,32,abs(',')]); % column delimiter +else + % make unique cdelim + cdelim = char(sort(cdelim(:))); + tmp = [1;1+find(diff(abs(cdelim))>0)]; + cdelim = cdelim(tmp)'; +end; +if nargin < 3, + rdelim = char([0,10,13,abs(';')]); % row delimiter +else + % make unique rdelim + rdelim = char(sort(rdelim(:))); + tmp = [1;1+find(diff(abs(rdelim))>0)]; + rdelim = rdelim(tmp)'; +end; +if nargin<4, + ddelim = '.'; +elseif length(ddelim)~=1, + error('decimal delimiter must be exactly one character.'); +end; + +% check if RDELIM and CDELIM are distinct +delim = sort(abs([cdelim,rdelim,ddelim])); +tmp = [1, 1 + find(diff(delim)>0)]; +delim = delim(tmp); +%[length(delim),length(cdelim),length(rdelim)] +if length(delim) < (length(cdelim)+length(rdelim))+1, % length(ddelim) must be one. + error('row, column and decimal delimiter are not distinct.'); +end; + +% check if delimiters are valid +tmp = sort(abs([cdelim,rdelim])); +flag = zeros(size(tmp)); +k1 = 1; +k2 = 1; +while (k1 <= length(tmp)) & (k2 <= length(valid_delim)), + if tmp(k1) == valid_delim(k2), + flag(k1) = 1; + k1 = k1 + 1; + elseif tmp(k1) < valid_delim(k2), + k1 = k1 + 1; + elseif tmp(k1) > valid_delim(k2), + k2 = k2 + 1; + end; +end; +if ~all(flag), + error('Invalid delimiters!'); +end; + +%%%%% various input parameters +if isnumeric(s) + if all(s<256) & all(s>=0) + s = char(s); + else + error('STR2DOUBLE: input variable must be a string') + end; +end; + +if isempty(s), + num = []; + status = 0; + return; + +elseif iscell(s), + strarray = s; + +elseif ischar(s) & all(size(s)>1), %% char array transformed into a string. + for k = 1:size(s,1), + tmp = find(~isspace(s(k,:))); + strarray{k,1} = s(k,min(tmp):max(tmp)); + end; + +elseif ischar(s), + num = []; + status = 0; + strarray = {}; + + s(end+1) = rdelim(1); % add stop sign; makes sure last digit is not skipped + + RD = zeros(size(s)); + for k = 1:length(rdelim), + RD = RD | (s==rdelim(k)); + end; + CD = RD; + for k = 1:length(cdelim), + CD = CD | (s==cdelim(k)); + end; + + k1 = 1; % current row + k2 = 0; % current column + k3 = 0; % current element + + sl = length(s); + ix = 1; + %while (ix < sl) & any(abs(s(ix))==[rdelim,cdelim]), + while (ix < sl) & CD(ix), + ix = ix + 1; + end; + ta = ix; te = []; + while ix <= sl; + if (ix == sl), + te = sl; + end; + %if any(abs(s(ix))==[cdelim(1),rdelim(1)]), + if CD(ix), + te = ix - 1; + end; + if ~isempty(te), + k2 = k2 + 1; + k3 = k3 + 1; + strarray{k1,k2} = s(ta:te); + %strarray{k1,k2} = [ta,te]; + + flag = 0; + %while any(abs(s(ix))==[cdelim(1),rdelim(1)]) & (ix < sl), + while CD(ix) & (ix < sl), + flag = flag | RD(ix); + ix = ix + 1; + end; + + if flag, + k2 = 0; + k1 = k1 + 1; + end; + ta = ix; + te = []; + end; + ix = ix + 1; + end; +else + error('STR2DOUBLE: invalid input argument'); +end; + +[nr,nc]= size(strarray); +status = zeros(nr,nc); +num = repmat(NaN,nr,nc); + +for k1 = 1:nr, +for k2 = 1:nc, + t = strarray{k1,k2}; + if (length(t)==0), + status(k1,k2) = -1; %% return error code + num(k1,k2) = NaN; + else + %% get mantisse + g = 0; + v = 1; + if t(1)=='-', + v = -1; + l = min(2,length(t)); + elseif t(1)=='+', + l = min(2,length(t)); + else + l = 1; + end; + + if strcmpi(t(l:end),'inf') + num(k1,k2) = v*inf; + + elseif strcmpi(t(l:end),'NaN'); + num(k1,k2) = NaN; + + else + if ddelim=='.', + t(t==ddelim)='.'; + end; + if FLAG_OCTAVE, + [v,tmp2,c] = sscanf(char(t),'%f %s','C'); + else + [v,c,em,ni] = sscanf(char(t),'%f %s'); + c = c * (ni>length(t)); + end; + if (c==1), + num(k1,k2) = v; + else + num(k1,k2) = NaN; + status(k1,k2) = -1; + end + end + end; +end; +end; +